Pension and Other Postretirement Benefits - Pre-Tax Information about Prior Service Cost and Net Actuarial (Gain) loss in AOCI (Details) $ in Thousands	12 Months Ended
Dec. 31, 2021 USD ($)
Public Service Company of New Mexico
Net actuarial (gain) loss
Experience (gain) loss	$ (5,700)
Public Service Company of New Mexico \| Pension Plan
Net actuarial (gain) loss
Amounts in AOCI not yet recognized in net periodic benefit cost (income) at beginning of year	132,078
Experience (gain) loss	(23,632)
Regulatory asset (liability) adjustment	11,797
Amortization recognized in net periodic benefit (income)	(8,181)
Amounts in AOCI not yet recognized in net periodic benefit cost at end of year	112,062
Public Service Company of New Mexico \| Executive Retirement Program
Net actuarial (gain) loss
Amounts in AOCI not yet recognized in net periodic benefit cost (income) at beginning of year	2,259
Experience (gain) loss	(657)
Regulatory asset (liability) adjustment	381
Amortization recognized in net periodic benefit (income)	(167)
Amounts in AOCI not yet recognized in net periodic benefit cost at end of year	1,816
Texas-New Mexico Power Company
Net actuarial (gain) loss
Experience (gain) loss	(1,000)
Texas-New Mexico Power Company \| Pension Plan
Net actuarial (gain) loss
Amounts in AOCI not yet recognized in net periodic benefit cost (income) at beginning of year	0
Experience (gain) loss	3,133
Regulatory asset (liability) adjustment	(3,133)
Amortization recognized in net periodic benefit (income)	0
Amounts in AOCI not yet recognized in net periodic benefit cost at end of year	0
Texas-New Mexico Power Company \| Executive Retirement Program
Net actuarial (gain) loss
Amounts in AOCI not yet recognized in net periodic benefit cost (income) at beginning of year	0
Experience (gain) loss	(211)
Regulatory asset (liability) adjustment	211
Amortization recognized in net periodic benefit (income)	0
Amounts in AOCI not yet recognized in net periodic benefit cost at end of year	$ 0

Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Net Actuarial (Gain) Loss, Regulatory Asset (Liability) Adjustment, before Tax

No definition available.

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- Definition

Amount, before tax, of accumulated other comprehensive income (loss) for gain (loss) of defined benefit plan, that has not been recognized in net periodic benefit (cost) credit.

+ References

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-Publisher FASB
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Amount, before tax, of gain (loss) for (increase) decrease in value of benefit obligation for change in actuarial assumptions and increase (decrease) in value of plan assets from experience different from that assumed of defined benefit plan, that has not been recognized in net periodic benefit (cost) credit.

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Amount, before tax, of reclassification adjustment from accumulated other comprehensive income (loss) for gain (loss) of defined benefit plan.

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